CHINA is set to quintuple the tax on the use of arable land for non-farming purposes and charge foreign-invested companies as much as their domestic peers in a bid to protect farm land and better control land supply, according to an ordinance released by the State Council yesterday. The instrument took effect from last Saturday and replaced the 1987 edition which had allowed foreign-invested companies to be exempt from the land use tax. The tighter requirements would give taxation a bigger leverage in protecting the country's land for cultivation.